Pneumatic piston pump



Sept. 22, 1936. A, BOYNTON n 2,054,924

PNEUMATIC PISTON PUMP Sept. 22, 1936. A, BYNTON A2,054,924

PNEUMATIG PISTON PUMP Filed DSC. 9, 1932 '4 Sheets-Sheet 2 Sept.z 22, 1936. y A BQYNTQN 2,054,924

PNEUMATIC PISTON PUMP Filed Deo. 9, 1932 4 Sheets-Sheet 3 A lexand r Boynto n 4 Sheets-Sheet 4 A. BOYNTON PNEUMATIG PISTON PUMP Filed Dec. 9, 1932 Sept. 22, 1936.

Patented sept. 22, i936 PNEUMATIC PISTON PUMP Alexander Boynton, San. Antonio, Tex., assignor to Chas. A. Beatty, San Antonio, Tex.

Application December 9, 1932, Serial No. 646,389

13 Claims.

My invention relates to devices for raising liquids from wells, particularly deep wells, by means of pneumatic pressure. i

It is an object of my invention to provide means for controlling the inlet of liquid to the eduction tube and to simultaneously control the inlet` of air or gas under pressure to raise the load which has been admitted.

I desire to provide a pressure sensitive device which will act to close the liquid inlet port and to simultaneously control the air inlet port so that only a predetermined load of liquid may be allowed to enter the eduction tube, and to then introduce the pressure uid to elevate the load 15 which has entered the eduction tube, and then to close the air or gas inlet port and simultaneously open the liquid intake port while another load or slug of liquid is being admitted into the eduction tube, and so on automatically. My invention embodies some of the features disclosed in my copending application, Serial No. 638,858, filed October 21, 1932, PatentedvJuly 3l, 1934, No. 1,968,633, but differs therefrom in that the liquid inlet and the air inlet are both operated 25 by the same element and at the same time. In

the description the term air is employed as referringto both air and/or gas.

It is also an object of my invention to provide a valve for the air inlet port which may be re- 30 tained in closed position-when the air or gas pressure in the pressure tube is below the predetermined value necessary to raise the load in the eduction tube, the air inlet valve being unseated by the pressure of the air or gas in the pressure tube.

It is a further object to provide a well head assembly which is adapted, with ylittle change, to accommodate different conditions of operation. i

In the drawings herewith Fig. 1 is a central, longitudinal section through the tubing employed with my device, and showing the. upper end of the control device employed with the invention.

Fig. 2 is a similar section showing the structure of the device below the portion shownin Fig. 1.

Fig. 3 is a central, vertical section through the liquid inlet control, shown partly in Fig. 1.

Fig. 4 is a transverse section taken on the plane 4 4 of Fig. 3.

)0^ Figs. 5, 6, and 7 are similar longitudinal sectional views showing separate modifications in the structure of the air and gas control valve.

Fig. 8 is a side view, partly in section, of the upper well head equipment,

Fig; 9 is a sectional detail of one form of latching device for the liquid intake valve.

Fig. 10 is a longitudinal section of another arrangement of well head equipment. Fig. 11 is a sectional detail of a diiferentform 0 of diierential valve.

Fig. 12 is a longitudinal section showing another form of well installation'which I employ.

Fig. 13 is a broken detail of one form of valve plunger.

Fig. 14 is a sectional detail showing another form of latching device.

Fig. 15 is a central vertical section through the ball cage member forming a part of -my latching device.

Fig. 16 is a bottom plan view of the same.

Fig. 17 is a top plan View of the ball rider; and

Fig. 18 is a side elevation thereof.

It is to be understood that my device is employed-within a well equipped with a well casing A, a casing head B thereon, and equipment at l5 the upper end of the well for introducing air into the upper end of the pressure tube I, and for sealing the pressure tube about the eduction tube 2, which is spaced inside said pressure tube'. The eduction tube in turn extends through the 20 sealing means C at the upper end of the casing head and has a uid tight fit therewith. This structure is disclosed in various forms in Figs. 8, 10 and 12, and will be later described.

The lower end of the pressure tube 2 is connected within a swaged coupling member 3. Said coupling is tapered downwardly and threaded on its reduced lower end `to engage within a tubular member 4 which is formed with openings therein at 5 to form a cage for the check valve 6. The lower end of the cage is closed by a threaded plug 'I. Above this plug is a spiral spring 8 upon which is supported a ball carrier 9, the upper end of which is recessed to receive the ball 6. The spring is under compression and tends to force the ball 6 upwardly to engage within a seat I0 fitted within the lower end of the coupling member 3.

The eduction tube is supported Within the coupling 3 by a seal ring II which is preferably' formed of lead or other soft metal poured in place or otherwise fitted on below the shoulder I2 on the nipple I3 near the lower end of the eduction tube, and is heldin more leak proof contact with the nipple by a series of grooves I4 in the side of the nipple I3. The lower end of said nipple I3 when in place projects beyond the valve` seat I 0, the lower end of the nipple engaging against the ball 6 and forcing it downwardly from its seat. Said nipple is slotted at I5 to allow the 50 yentrance of liquid into the tube.

Above the nipple I3 in the barrel I6 is th standing valve which may be employed when desired. Said valve is mounted within the barrel at its lower end, and is made up of a valve body I1 which has a leak proof t within the barrel, the valve seat ring I8, a ball valve I9, and a cage 29 secured to the body member I1. This is an ordinary type of standing valve, and need not be further described.

Above the barrel I6 is a barrel 2| in which is placed the valve operating mechanism. At the lower end of this barrel is secured a plate 22 forming a base holder for the bellows or multiple diasage 23 is beveled to provide a seat 24 for a valve 25. This structure is best disclosed in Fig. 3.

The valve 25 is mounted upon a transverse bar 26 secured to the lower end of a housing 21 which encloses the bellows or diaphragm by which the valve is operated. Said bar 26 is extended downwardly-about the shank of the valve and is beveled to an edge presented toward the incoming fluid. The housing 21 in closed at its upper end by an adjusting nut 23. Said nut has therein an axial opening to receive the screw29 upon the base of the air inlet valve support 30.

Within the housing 21 is the bellows shaped diaphragm 3l. Said bellows lis connected 'at the upper end with a ring 32 ,into which is screwed the head 33 upon the latching shaft 34. Said head overlaps the upper end of the ring, and may be secured rigidly thereto by a bond of solder or welding material 35 above said ring.

The lower end of the ring 32 has a downwardly extending flange 36 into which the upper end of the bellows is secured by solder 31 to provide a leak proof union.

As will be seen in Fig. 3, thelower end of the diaphragm 3 I is soldered to the upwardly extending flange 38 upon the latching barrel 39 to provide a leak proof union.

'I'he latching barrel 39 is provided with an inwardly extending flange 40 at its upper end to flt about the lower extension 4| upon the latching shaft 34. It has longitudinal passages 42 therethrough to allow the passage of liquid between the bellows member and the said latching barrel. The latching barrel is threaded at its lower end 43 to engage with the upwardly extending arms 44 on the base plate 22.

With reference to Fig. 4, it Will be seen that the base plate has an upstanding sleeve which is diametrically slotted longitudinally to provide two spaced arms 44 of semi-cylindrical formation. The upper ends of these two arms are threaded internally to engage the latching barrel, the slot between the two arms allowing vertical movement of the bar 26 on the lower end of the housing 21.

The latching barrel is closed at its lower end by an interior plug 46 which supports a spring 41 bearing at its upper end against 'aging 46 which forms a supporting base for the prongs of the ball rider which movably contact the latchbeveled at 5| to engage against the balls 49 and i tending to move them inwardly against the latching shaft extension 4l. Said extension has an upper peripheral groove 52 and a lower peripheral groove 53, said grooves being spaced apart by an approximately spherical portion 54 between them. The balls are held by the pressure of the spring 41 resiliently into latching engagement with a, shoulder of either the upper or lower groove, as will belater described. The ends of the grooves may 'be either arched or straight, preferably arched as shown in Figs. 3 and 9.

'I'he angle of the bevel 5l is very important in providing for proper movement of the balls 49. If this angle inclines more to the horizontal a stronger spring 41 may be used. vThis reduces friction and makes the latch action more snappy, due to the fact that less spring compression is required to permit outward movement of the balls.

The latch action may be made still more snappy by providing steeper grooves on the latch shaft extension than shown in Fig. 3, as appears in Fig. 9. This figure shows a straight section between the grooves to provide for proper travel ofthe latch shaft, which travel measures the valve travel.

In Fig. 9, I have illustrated a construction of the latching shaft which allows a slightly different action of the valve which is controlled thereby. It will be noted that in the lower groove 53 the shoulders at each end of the notch are made more abrupt sothat the ballsl 49 bear against a more abrupt shoulder. On the other hand, the upper notch 52' is shallower than the lower one and the shoulders at ea'ch end have a more gradual slope. A Further than this, the shaft extension between the two grooves has a portion 54 which is cylindrical and amounts to the grooves being spaced slightly farther apart. To produce a different latch action the grooves above described may be reversed, i. e. the upper groove shown may be placed below and the lower groove shown may nbe placed above.

Under certain conditions it may be best that the abrupt valve action should be in uone direction only. This may be accomplished by providing only one groove at the proper place on the latching shaft `as will be apparent by reference to Figs. 3 and 9 and as is specifically shown in Fig. 14.

With this arrangement it will be seen that when the latch is in its uppermost position as shown in Fig. 9, the balls will tend to latch it more securely in that position. However, when the` diaphragm tends'to contract to move the shaft downwardly to close the liquid inlet, the movement will be resisted by the bearing of the balls against the more abrupt shoulder at the upper end of the lower recess, but when this resistance has been overcome by the pressure of the liquid However, when the balls are in the upper recess the force tending torestrain the upward movement of the shaft is not so strong, because the shoulder is longer and more gradually sloped or rounded. When the shaft is moved in the upward direction it will also move abruptly, but less force will be required to produce the movement than when the valve 25 was moved to closed position. It will thus be seen that the action of my latching shaft may be varied not only bythe compression upon the spring 41, but by .various modifications in the form and positio'nof the recesses in the shaft forming the latch. Varying the diameter of the balls will also changethe force required to produce the valve movement.,V The larger the balls engaging the same shoulder thev less force will be required to produce themovement, and vice versa.

Another form of the latching device is shown in Fig. 14 in which a rgw of balls 49 rest upon thel lower atsurface of threaded plug 50, and are holder 3D.

held resiliently against latching shaft extension 4| by the upper circular'inclined surface of the ball rider 48' which is held in movable contact with the balls by the compression force of spring 41. The form of latching device shown in Fig. 14 operates substantially the same as was described for the form shown in Figs. 3 and 9.

The bellows diaphragm is of thin sheet metal of either spiral or ring type construction, and may be a single wall of metal or the wall may be made up of two or more layers of metal as may be necessary to form a bellows of the proper strength, resiliency, and durability. The bellows is held normally in extended position by an inner spring 55 which bears at its lower end against the flange 40, and at its upper end against the head 33A upon thelatching shaft. In assembling the device during the process of manufacturing, I ll the interior of the bellows diaphragm and the latching barrel with a non-corrosive lubricating liquid such as glycerine. Then I screw the latching shaft part way into the threads of the bellows top end connection, a vertical notch 32a beingcut or filed through said threads to allow passageway for fluid. I then compress the device longitudinally to about the length to which it will be compressed in its maximum compression in use. This will expel some of the glycerine through the vertical notch 32a in the threaded upper end. The bellows will then be allowed to expand, and there will be a cushion of air to take the place of the glycerine which was discharged. The upper end of the device may then be sealed by means of the bond of solder 35.

During the process of compressing the bellows in assembling as described, there will be a permanent set in the wall of the bellows which will prevent it from expanding to its original length. Furthermore, the spring 55 which is under slight compression when first assembled will be placed under further compression by the above mentioned permanent set of the bellows. The expansive force of the spring will tendto hold the bellows elongated.

I contemplate forming the grooves or notches 52 and 53 in the latching shaft extension after testing the assembly by compression of the bellows as previously noted. The exact position/ and travel of the latching shaft extension 4I willbe marked on the shaft extension by the compression force exerted thereon by the balls. This marking enables the grooves to then be cut in proper place to receive the balls 49. The shaft will thereafter be hardened so as to minimize wear in the use of the device. There are openings longitudinally through the ball retainer D to allow the circulation of the glycerine longitudinally therethrough.

The air inlet valve 56 is formed upon a stem 51 which is received' within a rec-ess in the valve There is a spring 58 within the recess and bearing upon the valve tending to hold it in closed position with a predetermined light pressure so that the said valve may be unseated by the air under pressure tending to enter the eduction tube when the liquid intake valve is closed.

The lower end of the recess in which the valve stem is, housed, has lateral openings 59 to allow the circulation of liquid therethrough to wash out sand or sediment tending to clog the action of the device.

' are mounted above .the adjusting plate 28 and The valve and vspring holder 30l provided for through a coupling fitting 60 which forms a coupling means between the eduction tube 2 and the upper end of the barrel 2 I. There is a radially extending inlet opening 6| in the wall of the coupling member, said inlet being extended axially downwardly at 62 and threaded to receive a valve seat member 63, the lower end of which provides a seat for the' tapered valve 56 previously described. Said valve is held normally seated by the spring 58, but may be depressed to open the air or gas passage by the pressure of the air or gas from the pressure tube. The liquid being pumped finds a passage through the coupling by means of an opening shown at 64. Within the coupling is a drop valve seat 65. Said seat may be screwed in, pressed in, or clamped between the shoulder under the seat in the upper end of the coupling and the eduction tube 2 when the same is connected with the eduction tube. This seat may be used to receive a ball valve or any other type of valve dropped from the surface when the device is to be withdrawn from the well.

In the operation of my device which has just been described, the parts will be assembled in the manner shown in the drawings. The pressure tube,| is inserted into the well with the check valve 6 fitting within its seat I 0, closing the lower end thereof. When the pressure tube has been properly placed in the well the eduction tube will then be inserted until the packing member H comes to'a seat in the coupling 3 and seals off the passage between the -two tubes. The lower end of the nipple I3 will have then engaged the valve 6 and forced it into the position shown in Fig. 2, and the liquid will then iind an inlet upwardly into the eduction tube.

When the head of liquid rises in the eduction tube, and about the diaphragm member, the weight of the head will gradually increase until sulicient pressure is exerted on the bellows or diaphragm to compress the same longitudinally. and thus close the liquid inlet valve 25 and leave the air or gas inlet in the seat member 63 free to be opened by the force of the pressure fluid acting on valve 56 and spring 58. If the type of air or gas inlet valves shown in Figs. 5 or 6 are used the air or gas valve will instantly open when the liquid intake valve closes because in Figs. 5 and 6 the air or gas valve is fastened to the bellows assembly. It will .be seen that as the lower end of the bellows member is held rigidly in position as shown in Fig. 3, the longitudinal compression of the bellows diaphragm will move the housing 2l and the valve 25 downwardly. The same compression Will move the upper valve housing 30 downwardly and thus4 leave valve 56 free to be moved downward from its seat by the air or gas pressure in the pressure tubing. If the air or gas pressure in the pressure tube should be less'than the Weight of liquid in the eduction tube valve 56 will remain held with slight force in its seat by the spring 58, but will unseat whenever the force of the air under pressure in the pressure tube exceeds the weight of liquid in the eduction tube. It will be noted that when the bellows or diaphragm is extended, the valve 56 will be held rigidly closed, but when said bellows or diaphragmjcontracts under load pressure to release the air or gas valve, the gas pressure will, if greater than the weight of the slug plus the force of the spring 58, at once unseat the valve 56. If there is not' suillcient pressure Uof air, the air valve will remain closed, and no liquid can escape into the pressure tube.

This action of the bellows or diaphragm willl -be made abruptly by means of the latchlng deair or gas valve in open position, at thesame 1 tirne closing the liquid intake valve. On the other hand, when the pressure within the eduction tube has been partially relieved to a predetermined value dueto the upward movement of the load of liquid and its partial discharge at the surface, the spring 55 within the bellows member will force the shaft again into the Fig. 3 position by an abrupt movement, similar to, but in reverse direction to that previously noted. This action may be varied by changing the form and relative positions of the grooves 52 and 53 or by using larger or smaller balls as previously noted. A

In its operationas described, the device will automatically admit into the eduction tube a slug of liquid of predetermined weight or length, then automatically close the liquid intake valve and simultaneously release the air or gas intake valve so that it may open and remain opcn until enough compressed air or gas has been admitted under the slug of liquid to expel it frcm the well. Both valves will move in unison, where suihcient pressure is present in the casing, one opening while the other is closing.

The valve controlling the air or gas inlet may be varied in many ways from the construction shown in Fig. 1. In Figs. 5, 6, and '7, I have shown other forms which, under certain conditions, may be preferable to that shown in the first embodiment. In Fig. '1, I have shown a structure which is not materially different from that shown in Fig. 1. There are certain structural differences, however. The drop valve seat 65 is shown as integral with the iitting 68.

Furthermore, the valve seat member 63 is ex tended downwardly, and the passage therethrough is enlarged toward the lower end at 61 to slidably receive the valve stem 68 upon the valve member 69. The seat is formed toward the upper end of thevmember 63 as shown at 10 and below the seat the member 63' is formed with radial openings 1l through which air or gas may enter the eduction tube. 1

Below the radial openings I have mounted a deflector 12.' This deflector is dished on its upper side to form a deflecting surface 13 which directs the air or gas upwardly away from the diaphragm It is contemplated by assembly below the valve. this structure that the air entering the eduction tube will \be deflected upwardly under the liquid slug and will by reason ofthe upward current produce a slight injector eiect tending tov reduce the pressure that would otherwise obtain in the bellows chamber.y :hector will prevent the inrushing air from retarding the action of the bellows in expanding when' the slug has been expelled to the extent that air or gas valve 69 should. close.

The valve stem 68 in this embodiment is mounted in the same manner as is the valve '16v having an upper seat 11.

This action of the destem 51, Fig. 1. However, a radial flange 14 is formed upon the valve stem against which the upper end-of'the spring 58 may bear tending to hold the valve in closed position. This form of the invention has the advantage of preventing the force of the incoming air or gas from being directed downwardly toward the diaphragm and exerting a back pressure thereon. Furthermore, considerable frictional loss is prevented by the air' being thus directed upwardly behind the rising slug of liquid. Plug Z may be removed to allow for adjustment of the valve action by engaging the slot 18 in upper end of nipple 63 with a screw driver or other similar tool.

In Fig. 6 a still different air and check valve mechanism is shown. This is the preferred type. The fitting 60a has been formed with an upper valve 15. The inlet 6|a leads to a valve chamber The valve 15y is tapered upwardly and connected with a stem 19, the upper end o f which is connected vWithin a nut and a lock nut 8l. Nut 8U serves as a bearing for a spring 82 which is supported at its other end upon a shoulder 83 forming the lower wall of the chamber 84 in which the spring is housed. Nut 80 will stop upon the shoulder below it in chamber 84, thus preventing valve 15 from seating upon the upper end of nipple 63a which seating is not desired in this construction.

There lis a lower opening from chamber 84 ing is relatively large to permit entrance of a screw driver or similar tool to adjust nipple 63a. by engaging slot 18 during the process of testing and adjusting before valve 6Ia, spring 82, and plug 86 are put in place. The spring acts to..hold the valve 15 resiliently but lightly into its upper seat closing the inlet, but is adapted to be moved from its seat by the pressure of the air or gas entering through the inlet 61a. The upper extension in which the spring and valve stem are housed, is closed by a plug 86.

The valve seat member 63a is formed with a valve seat 69a, radial openings 1l, and a deflector 12, in the same manner as has been described relative to the Fig. '1 embodiment. In this structure, however, the valve stem 68a is secured directly into the upper end 81 of the diaphragm assembly and is movable rigidly therewith. It is, therefore, adapted to be seated or unseated more positively by the movement of the diaphragm as has been previously described.

The valve 15 will prevent the passage of iluid from the interior of the eduction tube outwardly into the pressure tube whenever the iluid pressure in the pressure tube is lower than that within the eductiontube. It will, however, be possible to adjust 'the compression on the spring 82 so as to hold the valve closed with a predetermined pressure which will be overcome by the pressure uid, air or gas, as soon as this pressure reaches a predetermined value. By this means the pressure uvid can be prevented from entering the eduction tube at less than the predetermined value required to lift the slug.

In Fig. 5 the iitting 60h is arranged somewhat leading to the chamber 84h in which the spring 82h and nuts 80h and 81h are housed.

The valve stem 88h is of slightly larger diamis connected in the upper end 81 of the diaphragm assembly as in the previous embodiment, and the upper end thereof is tapered at 8912 to flt within the seat 92 at the lower end of the valve seat member 63h. It will be seen that this valve is moved positively to and from its seat 92 by the action of the diaphragm member as previously described under Fig. 6.

The valve plunger 88 is smaller than the valve chamber 1Gb, leaving a clearance which allows the passage of air in approximately the same amount as does the passage through the seat member 83h. This valve serves the purpose of a check valve to prevent the escape of fluid from within the eduction tube to the pressure tube when the interior pressures are in excess of those outside the eduction tube. Furthermore, when the flow of air or gas into the eduction tube becomes great, due to the partial discharge of the load of liquid, the force of the current of air or gas will force this valve into its lower seat' 90 and prevent the entrance of more pressure uid into the eduction tube.

In order that the valve 8.8 may be readily unseated when the control valve 69h is closed, I have formed a slot 9| at the upper end of the valve seat member 63h so that a small escape of air or gas past the valve plunger 88 may occur, sufficient to balance the fluid pressures above and below the valve plunger. This may also be accomplished by forming a slight groove 93 at the lower end of the valve plunger 88 as shown in Fig. 13. Either expedient may be adopted to provide for the buildingup of pressure below the valve plunger.

As disclosed in Fig. 11 a different means of unseating the valve plunger 88 may be employed by forming an axial recess 94 in the lower end `of the valve plunger and extendinga rod 95 upwardly from the valve member 69e so'lthat the closing of the valve 69o will tend to push the valve 88 upwardly out of its lower seat, and thus allow the fluid pressure on each end ofthe valve to become equalized and permit valve 88 to move to its upper seat.

In installing this invention various types of connections may be made at the upper end of the well. In Fig. 8 I have illustrated the arrangement whereby the well may be operated through gas produced by the well. The casing A is shown as/ connected to the casing head B having a pair of."

of'gas produced in the well over that necessary to flow the liquid from the well, I have shown an extension |03 on the T 99 which leads byway of a gate valve |04 to the relief valve |05. This valve may be of any desired construction and I have shown one similar to that disclosed in my co-pending application Serial No. 635,542, led September 30, 1932. 'This valve will act to open automatically when the pressure in the well at` tains a predetermined maximum and will allow the excessgas to pass off thru the line on the down-stream side of the valve. vBy this means enough pressure to flow the well may be held in the pressure tube and the surplus gas used for other purposes. Such use of the surplus gas will prevent excessive back pressure from being kept upon the producing formations thereby increasing the production of oil.

My well head in this embodiment is shown as having the casing head B closed by means of a flange |06 on the pressure tube fitting within a seat |01 in the casing head with a sealing member |08 between the plate and the seat which may be made of lead or other soft metal and adapted to be compressed into serrations'in the seat of the plate and casing head to form a fluid vtight closure, as will be apparent. The cap |09 is screwed on the upper end of the casing head and has an inner down-turned flange IIO which is beveled to an edge on its lower end for engagement against a packing ring I of some desired packing material such as lead or other soft metal. This provides the seal between the casing and the pressure tube so that no leak around the upper end of the casing head can occur.

It is contemplated that when air or gas .in the well is suiiclent but not in excess of. the amount required to flow the liquid out through the eduction tube, the openings in the casing head and the pressure tube may be closed as in Fig. 10 where I have shown the outlets in the casing head both closed by bull plugs 91.

Also the branch line connected with the pressure tube at is closed by means of a cap H2. The gas nds entrance from the casing to the pressure tube through openings I3 adjacent the hupper end of the pressure tube, the openings being staggered so as not to materially weaken the pressure tube. Thus in this embodiment the gas from the well rises in the casing and flows through the openings I|3 into the pressure tube and from there into the eduction tube in the manner previously described.

It is obvious that if gas in excessive amounts is encountered during the operation of this lnstallation it may be very readily converted into the form shown in Fig. 8 without appreciable difficulty.v Likewise, if lnsuilicient gas is produced by the well, pressure fluid may be supplied exteriorly by a connection into nipple l0 l, in which case holes ||3 will be closed.

In Fig. 12 I have illustrated how the use of a separate pressure tube maybe avoided. In this case the casing A answers the purpose of the pressure tube. I have closed the space below the air or gas inlet by a packer or lead seal |I4 placed at the upper end of. the liner and about the eduction tube extension H8. The packer may, however, be set at any other desired place in the casing above the liner by well known methods. This will confine the pressure fluid entering the casing thru lateral branch line 98a within the space l1 between the eduction tube and the casing and prevent the same from `contacting the producing formations of the well. The fluid pressure built up in the casing may then pass into the eduction tube by way of the air or gas intake' valve in the manner previously described. At the upper end of the well the eduction tube is extended through the casing head and sealed therewith in the same manner as is the pressure tube in the Fig. 8 embodiment.

It will be obvious that my device is capable of various modifications, both as to the manner of conducting the pressure fluid into the well for operating my lifting apparatus, and also as to the arrangement of the control valves by which the .of the pressure tube or casing depending upon the particular installation employed. See Figs. 8 and 10. The pressure will usually be supplied constantly and remain turned into the pressure tube or casing so that there will be a continual supply of air or gas under pressure available thereto. As the pressure tube is sealed at its lower end in the coupling 3, or by the seal H4, there will be no pressure exerted upon the liquid in the well by the air 6r gas in the pressure tube. The amount of air or gas, and the pressure at which it should be admitted intothe eduction tube, will dependfupon the size of the tube and the length of the slug of liquid, together with the physical rproperties of the liquid, the depth at which the `device is installed, and the frequency at which the slugs enter the eduction tube, or the frequency of expulsion desired, as for oil wells under proration.

Should the ordinarily constant pressure in the pressure tubing fail or be cut .off by any cause,

the air or gas intake valve shown in Figs. 1, 7, 10 and 12, becomes a check valve and prevents liquid from escaping from the ow tubing into the pressure tubing when the liquid intake valve closes. In Figs. 5, 6, '7 and 11 the check valve, to prevent liquid from escaping out of the eduction tube into the pressure tube at certain times, is separate from the air or gas intake valve as appears.y

.Provision is made whereby no fluid enters the pressure tubing as lt is lowered or run into the Well, and the ow tubing may be lowered into and withdrawn from thepressure tubing at will without allowing uid to enter the pressure tubing. Were it not for this provision to keep the pressure tubing dry inside, great pressure would be required to start a well that heads up to a high level. With this provision the rst slug is uniform with all others. The well will, therefore, start on the same pressure that will be required to operate it after starting, unless the check valve feature is eliminated.

If the liquid to be liftedI is thin or light, and of a character that allows air or gas to break into or through the slug, a different or heavier liquid, semiliquid, or gelatinous substance may be admitted into the pressure tubing in order to provide that such different or heavier liquid, semiliquid, or gelatinous substance will be forced down the pressure tubing and form a piston-like bottom to or under the slugto prevent or minimize such breaking into or through the slug by the air or gas that expels it.

not only strong and resistant to external pressure but is sensitive to changes in pressure so that it The multiple diaphragm which I employ is will function accurately to control the valves.

'I'he maximum compression travel of a bellows (unless the travel is sooner arrested by a liquid filler as will be hereinafter discussed) is always the sum of the distances between the internal walls ofthe several corrugations, these distances being measured along a line parallel to the lengthwise center line of the bellows, and at such distance from said center line as will intersect each corrugation where. the opposing walls would rst touch if compressed by external pressure. This maximum compression travel of a'metallic bellows such'as shown is approximately 30 per cent v tory for the purposes of this invention. Maximum working travel as provided in the device for extremely high pressures will practically never occur. the usual working travel being from 1/50 to 1/30 of the bellows length. Under such working conditions such a bellows has proven extremely durable.

Glycerine or other lubricating liquid should always be placed in the bellows up to slightly below the level of its maximum travel, leaving an air pocket to occupy the space between the glycerine and the top of the bellows. This air pocket becomes a cushion which yields to all compression force upon the bellows. and the liquid ller serves to arrest the compression travel. The travel thereby permitted is the maximum working travel above mentioned. 'Ihe bellows assembly will also function eiciently if a partial vacuum be above the glycerine instead of the air pocket. The bellows then cushions upon the spring and glycerine.

The fact that a bellows, assembled as shown in Fig. 3, will function properly under all pressures is due to the fact that too much compression is prevented by the liquid ller. Without the liquid filler extremely great pressure'exterior of the bellows would, of course, collapse and destroy the bellows. With the liquid filler of proper length no pressure will ever be encountered in any well which the bellows will not safely withstand without damage.

It does not appear to be known that a bellows,

such as shown in Figs. 1 and 3, when assembled as herein specified, does not, in fact, resist high pressure wholly from without because the pressure inside is always equal to the pressure outside, vless only the expansive force of the spring. To illustrate: if the bellows in assembly be filled with glycerine to within one inch ofthe top, and the spring would compress one inch under 100 pounds per square inch applied externally to the bellows; then there would never be more than 100 pounds difference between" the external and internal pressures, assuming the force required to compress the bellows itself to be negligible. If,

rthen, there should be 10,000 pounds per square inch of external pressure there' would be 9,900

pounds of internal pressure, leaving a net force of only 100 pounds per square inch acting externally on the bellows. The bellowsv wall thus becomes impinged between two uid forces, the external of which can never exceed the internalA by more than 100 pounds regardless of how great y -.030 inch,- it is apparent. that this type of construction will safely withstand the highest pressures to be encountered. v l

A metallic bellows, either spirally or horizontally corrugated, is in fact nothing'more or less than a multiple diaphragm. The travel of each corrugation multiplied by the total number of corrugations in the bellows equals the total travel; whereas a, simple diaphragm must accomplish its total travel in what is mechanically equal to one-half of a corrugation. A bellows having 50 corrugations, each corrugation ilexing .020 inch, that is .010 inch on each side of each corrugation, can be constructed ofvery small diameter and will travel one inch. Consequently such a bellows will have long life in service; whereas a diaphragm having one inch travel will be impossible to construct of a small diameter, and will have short life inservice if constructed of any diameter less than many times the diameter of a bellows that will afford the same travel. Small diameters in all parts being necessary in constructions to be used where space is limited, as in a welltubing, renders the multiple corrugation bellows practical, and the single diaphragm impractical for such uses.

The free length of the spring 55 should be considerably longer than the free length of the bellows in order that the force required tocompress the spring in the assembly will vnot increase as the spring is compressed as rapidly as this force would increase were the spring stronger and the free length of the. stronger spring equal to or not appreciably greater than only limitationis that the force required to com- Cil press the spring must not be greater than the external force that would rupture the bellows. But since a bellows having a wall thickness of .008 inch with no liquid inside, and containing a spring that required 250 pounds to compress 1' inch, has been repeatedly tested with external hydraulic pressures up to 5,000 pounds per square inch without damage, it appears that the above limitation is more theoretical than actual.

The air inlet valve 56. as previously noted, acts to prevent liquid from passing out of the ow tubing into the pressure tubing if there should be inadequate pressure in the pressure tubing to lift the slug of-1iquid when it has entered the flow tubing and compressed the bellows and thereby closed the liquid intake valve. If there is enough pressure in the pressure tubing to lift the slug this pressure will compress the weak spring under the combination air or gas and check valve and allow the compressed air or gas to enterthe eduction tube. But if there should not be enough pressure in the pressure.

check valve.

The check valve will then change its function to' that of the air or gas intake valve. The check valve, by keeping liquid from entering the pressure tubing, provides that the slug to be expelled is always of the same weight or length. The same pressure ordinarily used to produce liquid from the well by this method will also start the well after any failureor interruption of pressure in the pressure tubing. In Fig, 5, check valve 89, and in Fig. 6, check valve 15, and in Fig. l1, check valve 88, are separate from the air or gasA intake valve, but both function to accomplish the same result as above described when the air or gas valve in Fig. 1 is acting as a check valve.

The volume and pressure of air or gas admitted by the air or gas intake valve should be regulated so asl to expel the slug at proper velocity.

The air or gas valve should slam wide ope to lift the slug as a Whole rather than aerate it. as would be done by slow or partial opening oi this valve. The air or gas valve should remain wide open to speed up the movement of the slug until such time as the air or gas under that part of the slug still remaining in the flow tubing will completely expel it from the well. The air or gas valve should then slam shut to provide a tight seal oi against the admission of pressure uid while the next slug of liquid is being admitted. d

The air or gas intake valve is adjusted to close, and the liquid intake valve to simultaneously open, before all of the slug has been expelled, because the compressed air or gas under that part of the slug still in the flow tubing will continue to expandunder the lightened and continuously lightening load, and thereby expel the remainder of the slug. Such simultaneous movement of the two valves causes a gentle puff of air or gas to follow the slug; whereas a hard blow, with resulting loss of energy. would follow the slug if the entire slug were expelled before the air or gas valve closes.

When the liquid intake valve is open, the latching balls engage or ride upon the lower half of the convexed circular surface between the two grooves'in the latching shaft as shown in Fig. 3, for the purpose of holding the liquid intake valve wide open and the air or gas intake valve completely closed until the entire slunr has entered the tubing, at which time the nqui intake valve will slam to its closed position while the air or gas intake valve simultaneously opens. When the liquid intake valve is closed the balls engage or ride upon the upper half lof the convexed l,

spherical lsurface between the grooves for the purpose of holding the liquid intake valve firmly closed and thetair or gas intake valve wide open until the slug of liquid has been nearly expelled from the ow tubing, at which time the liquid intake valve will again slam wide operi while the air or gasI intake valve simultaneously closes,

` and so on.

The action of the latching device may, howl,

ever, be modied from that described in thepreceding paragraph. as was described under the discussionl of Figs. 9 and 14.

It will be observed that my' device may be easily adjusted to operate accurately to allow only a limited load of liquid to enter the eduction tube` and to then admit air under pressure sufficient to raise the load so admitted; and further that when the load has been raised and party of it has been discharged, the consequent release of the pressure at the bellows diaphragm control member will allow the liquid inlet valve to open and the air inlet valve to simultaneously close again,

` and that the expansion of the air or-gas already to the manner in which the control device operates, and also to the presence of the standing valve I9 previously noted.

Having described my invention, what I claim is: 1. A fluid lift device for wells including a pressure tube, an eduction tube therein providing a passage for pressure iluid between them, a seal y closing the lower end of said passage, a liquid inlet at the lower end of said eduction tube, a valve in said inlet, an inlet for gaseous pressure fluid to said eduction tube above said liquid inlet, a fluid inlet valve therein, and means actuated by liquid pressure to control both said valves to close said liquid inlet and open said gaseous pressure fluid inlet simultaneously by a relatively high liquid pressure and then by a resulting relatively low liquid pressure to close the gaseous pressure uid intake and open the liquid intake at one end simultaneously, and additional means to close said pressure inlet opened by the force of said pressure fluid, this cycle of operation being a utomatic and continuous.

2-A fluid liftdevice for wells including a pres-` sure tube, an eduction tube therein providing a passage for pressure uid between them, a seal closing the lower end of said passage, a liquid inlet at the lower end of said eduction tube,"a valve in said inlet, an inlet for gaseous pressure fluid to said eduction tube above said liquid inlet, a liquid inlet valve therein, and means actuated by a certain predetermined maximum and minimum iluid pressure outside said means due to the head of pumped liquid to control vthe automatic alternate opening and closing of both said valves when a predetermined head of liquid has entered or been discharged from s'aideduction tube.

3. A fluid lift device for wells including a pressure tube, an eduction tube therein providing a passage for pressure fluid between them', a seal closing the lower end of said passage, a liquid inlet at the lower end of said eduction tube, a valve in said inlet, an inlet for pressure iluid toW said eduction tube above said liquid inlet, a fluid inlet valve therein, and means responsive to increased fluid pressure in said eduction tube to decrease the pressure tendingto close said pressure fluid inlet valve and simultaneously to close the liquid inlet valve, said pressure fluid acting alone to then open said pressure fluid inlet valve.

4. A fluid lift device for wells including a pres-V sure tube, an eduction tube therein providing a passage for pressure fluid between them, a seal closing the lower end of said passage, a liquid inlet at the lower end of said eductin tube, a valve in said liquid inlet, an inlet for gaseous pressure fluid to said eduction tube above said liquid inlet, a gaseous pressure fluid inlet valve therein, and a uid pressure responsive element acting through pressure of the head of liquid in said eduction tube and connected with .both of said valves to open the liquid inlet and close the gaseous pressure uid inlet until a predetermined load of liquid hasenteredZ the eduction tubeand .fluid-to open said uid inlet valve and enter said eduction tube, this cycle of the operation being automatically repeated as often as the liquid load isexpelled from the eduction tube.

5. A iluid lift device for wells including a pressure tube, an eduction tube therein providing a passage for pressure fluid between them, a seal closing the lower end of said passage, a liquid inlet at the lower end of said eduction tube, a valve in said liquid inlet, an inlet for pressure fluid to said eduction tube above said liquid inlet, a uld inlet valve therein, and means to close said liquid inlet, a-nd to also release said pressure fluid inlet valve, additional means acting to hold said pressure fluid inlet closed but acting to allow said inlet to open and allow entrance of pressure fluid below the liquid in said eduction .tube in response to pressure of said fluid.

6. In a iluid lift device, anL eduction tube, a liquid inlet'thereto, an air inlet abve said liquid inlet, means to conduct air under pressure to said air inlet, a housing between said inlets, a uid pressure responsive element in said housing, a. valve at each end of said element, each valve engaging within one of said inlets, said element exerting aeconstant valve closing pressure and thus being adapted to open said air inlet and close said liquid inlet valves when a predetermined head of liquid has entered said eduction tube to overcome said valve-closing pressure and means controlling the action of said element to cause'the valve movement to be rapid and abrupt in both directions.

7. In a iluid lift device, van eduction tube, a liquid inlet thereto, an air or gas inlet in the wall of said tube, means to conduct air or gas to said air or gas inlet, means to prevent the downward movement of fluid in said tube, and means responsive to a certain predetermined head of liquid in said tube to close said liquid inlet and open said air inlet simultaneously.

8. In a iiuid lift device, an eduction tube, a liquid inlet therto, an air or lgas inlet in the wall of said tube, m'eans to conduct gaseous fluid to said air or gas inlet, means to prevent the downward movement of fluid in said tube, and means in said tube and adapted to be acted upon by a c'ertain predetermined head of liquid in said tube to simultaneously close on the entrance of liquid and open the entrance for pressure uid to said tube.

9. In a uid lift device, an eduction tube, a liquid inlet thereto, an air or gas inlet in the wall of said tube, means to conduct air to said air or gas inlet, means to deflect the air upwardly in said tube from said air inlet, means to prevent ilow of 'fluid from said tube outwardly through said inlet, and means in said tube and adapted to be acted upon by the head of liquid in said tube to simultaneously close ofi the entrance of liquid and open the entrance for pressure iluid to Said tube, and a separate valve in said pressure fluid inlet operated to open by pressure of gaseous uid.

10. In a iluid lift device, an eduction tube, a liquid inlet thereto, an air or gas inlet to saild tube above said liquid inlet, means to conduct gas fromthe well to said air or gas inlet, means to regulate the pressure of said gas, an element in said tube between said liquid and gas inletsresponsive to the head of liquid in said tube, and valves controlled by said element to close said liquid inlet and decrease the pressure on said air or gas inlet simultaneously, said air or gas pressure then acting to open said gas inlet, and to again close said air or gas inlet and open said liquid inlet.

1l. A method of owing liquids from a well thru an eduction tube, comprising admitting a predetermined load of liquid into said tube, closing off the further entrance of liquid, simultaneously opening an inlet for gaseous fluid into said tube beneath said load, introducing into said 'liquid a charge of colloidal material above said gaseous uid, and, by means of expansion of the gaseous fluid, raising said load to the surface.

' 12. In a fluid pressure responsive element, a housing, a multiple diaphragm within said housing, means and secured at one en'd thereto outside said housing to rigidly support said diaphragm at the other end thereof, valve members at each end of said housing, a latching shaft secured to one end of said diaphragm and extending longitudinally of said diaphragm, and latching means resiliently engaging said shaft at its free end to hold said shaft releasably in adjusted position. v

13. In a fluid pressure responsive element, a housing, a multiple diaphragm within said housing, means and secured at one end thereto outside ALEXANDER BoYN'roN. 

